1. Field of the Invention
The present invention relates to the field of measuring devices and more particularly to a novel ruler for measuring the length of an object wherein the ruler includes a sliding cursor having magnifying means carried thereon for visually enlarging numerical indicia for the convenience of the user.
2. Brief Description of the Prior Art
In the past, it has been the conventional practice to employ an elongated ruler having spaced increments carried along one edge, which are related to numerical indicia carried along the midsection of the ruler but related or associated with each one of the respective measurement increments. Since it is desirable to display as many increments as possible within a given measurement distance, the size of the increments is very small and the associated numerical indicia with each of the increments is small and difficult to accurately discern. Many mistakes have been made in associating numerical indicia incorrectly with measurement markings that are not properly related due to the small size of the increments and the indicia.
Some attempts have been made to enlarge the numerical indicia by providing a magnifying glass which is used in one hand while the user holds the ruler in the other hand. Obviously, this is inconvenient and restricts the user so that pencils, writing implements or other implements cannot be used during the measurement procedure. In other instances, the magnifying glass has been elaborately placed on a separate device which is manually positioned over the ruler while a measurement is being taken. Inasmuch as the magnifying device is not carried on the ruler, loss or misplacement of the device oftentimes occurs and registration of the device with the ruler and its increments, as well as numerical indicia, is manually required by the user. In other words, since the magnifying device and the ruler are two separate items, there is no alignment or guidance means corelating the two devices for the convenience of the user.
Therefore, a long standing need has existed to provide a novel combined ruler and magnifying means that includes alignment and guidance means so that the magnifying means can be properly disposed so as to corelate measurement increment markings and numerical indicia. Display of the magnified numerical indicia should be augmented so that associated or other indicia on opposite sides of the selected numerical indicia are obscured or not magnified whereby the selected numerical indicia is magnified solely.